It's the restaurant's Roast Beef n' Cheddar sandwich with a stack of curly fries on top and it's FANTASTIC!
Here's the sandwich description from the Arby's website:
The Arbynator has Roast Beef, Cheese Sauce, Horsey Sauce®, Arby’s Sauce® and Curly Fries, all in the same sandwich. Or in other words, it is the most Arby’s sandwich Arby’s has ever made. Available in Classic, Double and Half Pound sizes.
I went with the classic version in this taste test and the sandwich was a delight with every bite! The stack of roast beef, the cheddar sauce, complimented by the marriage of Arby's and Horsey sauces, topped with those crunchy on the outside, tender on the inside curly fries and served on that sesame seed bun...... WOW did this sandwich hit the spot!
The sandwich ROCKS and I got curly fries in every bite!
I purchased my Arbynator Classic for just $4.50 (that's with tax) and it's a meal all by itself, totally satisfying.
The Arbynator gets five out of five Bachelor on the Cheap stars and is most definitely a repeat buy!